Keep the line input mode prompt on the local screen after input

It is for visibility.
Note: This line input mode prompt is not recorded by tio's logging
function.

src/readline.c

@@ -39,6 +39,17 @@ typedef struct readline_s
     int escape;
 } readline_t;
 
+void print_prompt(readline_t *rl)
+{
+    clear_line();
+    printf("%s", rl->prompt);
+    printf("\r"); // Move the cursor back to the beginning
+    for (int i = 0; i < rl->prompt_length; ++i)
+    {
+        printf("\x1b[C"); // Move the cursor right
+    }
+}
+
 void print_line(readline_t *rl)
 {
     clear_line();

src/readline.h

@@ -32,3 +32,4 @@ void readline_set_prompt(readline_t *rl, const char *prompt);
 void readline_prompt_for_input(readline_t *rl);
 void readline_input(readline_t *rl, char input_char);
 char *readline_get(readline_t *rl);
+void print_prompt(readline_t *rl);

src/tty.c

@@ -3274,6 +3274,7 @@ int tty_connect(void)
                                     {
                                         // Carriage return
                                         readline_input(readline_ctx, input_char);
+                                        print_prompt(readline_ctx);
 
                                         // Write current line to tty device
                                         char *rl_line = readline_get(readline_ctx);